


X-Rays

by Vienamarie



Category: Undertale (Video Game)
Genre: F/M
Language: English
Status: Completed
Published: 2016-06-19
Updated: 2016-06-19
Packaged: 2018-07-16 02:42:08
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 1,811
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/7248838
Author URL: https://archiveofourown.org/users/Vienamarie/pseuds/Vienamarie
Summary: <blockquote class="userstuff">
              <p>You get sick, and visit the hospital for a checkup. Sans discovers you've got bones under your skin. Fem!Reader</p>
            </blockquote>





	X-Rays

**Author's Note:**

  * For [Lavender_chan](https://archiveofourown.org/users/Lavender_chan/gifts).



Drabble trade!

 

Sans was smart.

He'd worked on the core before you were around, was obviously exceptional friends with Alphys, and you think he mentioned that he had several degrees once. It was clear he was more than just the lazy bag of bones Papyrus affectionately claimed him to be.

But if he was so smart, why didn't he know anything about the human anatomy?

You'd been dating the monster for close to ten months, now. Learning how to kiss a skeleton sure was something, but that was pretty much all you did. He kissed your lips or your cheeks or your forehead and you kissed his teeth or his cheekbones or the top of his skull. You were fine with that; going slow was good. 

But you were crawling along at a narcoleptic snail’s pace.

You had needs. Sans probably had needs, although they were less apparent. You two shared a bed but neither of you was bold enough to make a move. And you were going to change that, you swore! But the day you tried, you developed a horrendous upper-respiratory infection, and now you were in the hospital getting your chest x-rayed. The nurse had your bones visible on the screen as you laid on the table and held still for her. Another few examinations later, you were heading home with a prescription and the copies of your x-rays under your arm. 

That was how Sans found out you had bones underneath your flesh a week later, and he was absolutely enthralled. 

“____!” He exclaimed from your shared bedroom, startling you. You got off the couch and walked upstairs, opening the door to see him balking at the photos of your ribs. “What is this!?”

“It's...me?” You shrugged. You were better by now, nothing but a slight cough remaining, but you’d forgotten about your file. “What's the big deal?”

“The big -” he said, looking up at you. The lights acting as his pupils were blown wide and bright. “You have bones! Underneath your skin!”

“Yeah, well if I didn't, you'd be dating a blob…” You snorted, and suddenly he was on you. 

Sans stood, the folder of x-rays forgotten, and grasped your hand. He held it close, pressing lightly into the skin and letting out a surprised noise as be felt your phalanges. You chuckled, because this was adorable.

“Sans, did you really not know?” You asked. He shook his head.

“No, I...I just assumed humans were all muscle and organs and skin.”

“That doesn't make any sense, not even anatomically. Aren't you like a doctor five times over?” You asked.

“Six.” He said, pressing his fingers into your arm, now, and working his way up. “But they're for other sciences. I don't know a lot about human anatomy…”

You supposed that made sense. The first time you woke up and found out you had accidentally stained his sheets from your period, he thought you were dying. That was an embarrassing ordeal for the both of you. You were pulled out of your thoughts when his poking and prodding reached your shoulder. 

“I can't believe I didn't feel any of this before…” he breathed, fascinated. You snorted.

“You would've if you would touch me.” You blurted, and the both of you halted. Your cheeks became red and his cheekbones flushed a faint blue. 

Intimacy was a challenge, especially given that you weren't the same species. You didn't even know where to begin in terms of pleasuring the skeleton, and you could assume he was in the same boat when it came to you. 

“Do you want me to touch you, ____?” He asked. The tone of his voice made you shudder. The lights in his eyes were smaller, but more focused, as opposed to the hazy appearance they had a minute ago when he was mentally reciting the bones in your arm. You felt yourself nodding, and didn't protest when he began nudging you backwards to the bed. 

With a flick of his eye, the door closed and locked to prevent Papyrus or anybody else from accidentally walking in on you. 

The confidence Sans had worked up when he was guiding you onto the mattress went away as soon as he looked over your body. He appeared at a loss, and you were kinda confused, too.

“Sans,” you said quietly, reaching up to touch his cheek. His eyes met yours attentively. “If you don't want to -”

“That's not it.” He said. “Of course I want to touch you, I've wanted to touch you for months.” Hearing that sent a spark of heat between your legs, and you shifted underneath him. “I just don't...want to make a mistake. Or hurt you, or…”

“You won't.” You said. “I'll tell you if you are. And…” You lightly traced his sternum through his shirt. “You tell me if...if I hurt you, too, okay?”

Sans nodded, and then you two began exploring one another. It had started off sexual, but then it melted away into just curiosity. You were questioning each other for hours.

 

“Can you feel your bones?”

“I never thought to, not really. I don't think I can. All the tissue and muscles over top have all the nerves in them. What about you? You're all bone, can you feel me?”

“Yes. I guess I just do that without the rest of that stuff. Why do you have more skin some places and less in others?”

“That's just how my body is made, I guess? More skin for tougher areas and bigger muscles. I don't think I need a bunch of eyelid skin like I need thigh skin, you know? That would be weird.”

“Yeah, that makes sense. I don't even have eyes.”

“Yeah, how does that work?? Are those lights like...your pupils?”

“I guess?”

“Can you see in color?”

“Yes, I can see everything. Can I touch your eyes?”

“No, that would hurt. Can I touch your eye sockets?”

“Yeah, go ahead. Can I touch your tongue?”

“Sure... ‘ow ‘o ‘ou speah’ wi’-houth ope’i’g ‘our ‘outhhh?”

“Heh. I don't need to open my mouth to speak. I use magic.”

“Does your mouth open?”

“To an extent. Wanna see?”

 

On and on the questions continued. You had to tell Sans that certain areas of your body were a little sensitive to just blindly start groping (your eyes, your throat, your breasts…) And he had to tell you what parts made him uncomfortable, too (the insides of his sockets, his tailbone, his shoulder blades…). The clock read five thirty in the morning by the time you two were finished. Too tired to do anything even remotely sexy by now, the both of you collapsed on top of one another and passed out. 

After you woke up, though, you were pleasantly surprised to find that Sans had removed your panties and discovered where your clit was, even if he didn't exactly know what it did. You shifted your legs and puffed out a breath of air, and he noticed you were conscious.

“Hey, what's this?” He asked you, pressing his index phalange right against your button. You couldn't help the moan that left your mouth and he froze.

“Did that hurt!? I'm sorry, I -”

“Do it again.”

Sans blinked his sockets, a sight that would never not fascinate you, and slowly did it again. You groaned and shifted your hips up to meet his hand.

“Oh.” He said, smirking. “You aren't in pain…”

“No, I'm not…” You agreed, reaching up to grasp his free hand. “Can I...can I touch you, too?”

“Last night wasn't enough?” He joked, even though he was being a hypocrite as he fondled your nether regions. You rolled your eyes and sat up.

“I mean, can I make you feel good, too?” You rephrased. It was two questions, really. You wanted to know if you could touch him and if he was even capable of experiencing arousal. Sans seemed to understand, taking a moment to think of his answer.

“I probably don't get off the same way humans do, but I can.” He said slowly. “I'm not...y’know, full of fluids or anything.”

“Can I try?” You asked. “I don't want to be the only one that feels good, that's not fair.”

The skeleton smiled. “You can try.” He agreed, lying down and pulling you with him. “Go to town, baby doll.”

Turns out, skeletons could get off, and boy was it enthralling to witness. Sans didn't have a dick but that doesn't mean his fingers didn't do a hell of a good job thrusting in and out of your pussy. The sensation of being fingered without any skin to cushion his bones was an odd one, but that only served to make you wetter. Sans liked discovering that you could get wet in the first place, the fluid coating his hand.

He, on the other hand, was a different story. You found out fast that he was loud, and you loved it. Running your tongue over his clavicles elicited very positive responses, and threading your fingers through the spaces between his ribs made him groan and arch upwards into you. His pelvis was your favorite place to explore. Groping the bones there made him buck like a horse at a rodeo, and when his hips collided with yours it made the both of you cry out. That, combined with his fingers moving in and out of you, sent you over the edge had you collapsing on top of him, thrusting into his palm and mewling his name as your orgasm ran through you.

“F-fuck, ____!” He whined. He loved listening to you, too, and from the looks of it he was close as well. 

You licked a long, hard line along the length of his sternum and that seemed to do it for him. The lights in his eyes went out and his jaw parted, stilling, before he went slack again and let out a few harsh breaths. His fingers left you and you rolled off of him with a huff.

It took him a minute to recover, his pupils returning and looking at you with a level of affection that had you blushing. He smiled and reached over to pull you against his chest, a noise of contentment leaving him. 

“That was…” He said, laughing a little. “Damn, can we do that every morning?”

You laughed, too and nuzzled his cheek bone. “I dunno if I have the energy to do that every morning, but we can definitely do that again…” you said. Sans was satisfied by that response. 

“Can we stay in bed all day?” The skeleton asked. 

“I'm inclined to agree.” You nodded, mostly because you didn't trust your legs to support you after that. 

To think; all you’d needed to do to get physical was get some x-rays.


End file.
